Actin dynamics and force generation against a budded yeast particle. The cell expresses LimEΔ- GFP to label filamentous actin. (a) Time series showing the actin label in green superimposed on the greyscale brightfield image. The cell interacts first with the budded yeast on the right (circles indicating mother cell and bud), strongly accumulating actin around its neck. While this particle is released, the particle on the left (dots) is attacked in the same manner, again unsuccessfully. A second attempt on the first particle leads to severing of the linkage between mother and bud. Time is indicated in seconds. The complete series is shown in Additional file 1. (b) Particle movement before and after the severing event. Positions of the two halves of the particle are indicated at 4 second intervals from yellow through red to blue starting at 883 s of the sequence in (a). The cell border is indicated as a black contour. Whereas the outer part of the particle stays in place, the internalized one is moved about within the cell after severing of the linkage. Bars = 10 μm.